Machine of the rotary piston type



Sept. 5, 1967 R. LOESCHER 3,339,532

MACHINE OF THE ROTARY PISTON TYPE Filed Nov. 10, 1965 5 Sheets-Sheet 3 P1967 R. LOESCHER MACHINE OF THE ROTARY PISTON TYPE 5 Sheets-Sheet 2Filed Nov. 10, 1965 p 1967 R. LOESCHER 3,339,532

MACHINE OF THE ROTARY PISTON TYPE Filed NOV. 10, 1965 5 Sheets-Sheet 5Sept. 5, 1967- I R. LOESCHER v MACHINE OF THE ROTARY PISTON TYPE 5Sheets-Sheet 4 Filed Nov. 10, 1965 p 1967 R, LOESCHER MACHINE OF THEROTARY PISTON TYPE 5 Sheets-Sheet 5 Filed NOV. 10, 1965 Fig.6

Fig. 7

United States Patent Claims. ((51. 123---:;

My invention has for its object a machine of the rotary piston type andmore particularly an itnernal combustion engine of the rotary pistontype wherein the rotary piston provided with a plurality of arms orsides defines, as it rotates, a number of variable volume chambersinside an annular casing enclosing said piston and closed on both sides,said casing being provided with an incurved runway in contact with whichthe projecting sections of the piston are engaged, while a succession oflongitudinal portions of said runway extending along different angulardirections form, at the opposite ends of a horizontal diameter, alingedwedge-shaped sections facing each other or away from each other.

In all known machines of such a type, it is necessary to locateeccentrically the axis of the rotary piston and to provide a mechanismincluding an eccentric member and toothed wheels.

Now, my invention has for its object to provide an arrangement whichcuts out the necessity of locating eccentrically said axis of the rotarypiston.

According to my invention, this result is achieved primarily through thefact that the annular casing is shiftable with reference to the rotaryaxis of the piston so as to define, in association with the piston, thesuccessive chambers reaching, for either extreme position of the path ofsaid casing, the position corresponding to a minimum volume and forwhich the mixture is ignited, while the thrust exerted on the arc of theannular casng limiting said chamber of a minimum volume urges the wedgeshaped section of the annular casing runway diametrically opposed tosaid first-mentioned are against an apex of the piston and transmits arotary torque to the latter.

This arrangement, according to my invention, allows retaining a centrallocation for the rotary axis of the piston. The primary advantage of myinvention consists in fact in that more favorable torque conditions areensured through the action of the wedge-shaped projections, that it ispossible to obtain a more favorable shape for each chamber, that the arewhich is nearest the axis acts after the manner of a piston in acylinder and forms a chamber wall adapted to execute a rectilinearmovement and finally that the yield is improved by reason of the minimumvolume chamber expanding speedily as a consequence of the angularshifting of the piston.

In the accompanying drawings, I have illutsrated a number of embodimentsof my improved machine. In the 7 figures of said drawings:

FIG. 1 illustrates an arrangement for executing the curve defining therunway inside the annular casing,

through the agency of the eccentric member 3. Said carriage carries thetoothed wheels 5 and 6 which engage each other with a speed-reducingratio 1:3 and it carries also a rocking arm 7 carrying in its turn atailed cutter 8 through the agency of the spindle 9 carrying saidcutter. The rocking arm carrying the cutter and which is subjected to ashifting under the action of the reciprocation of the carriage and ofthe rotation of the toothed wheels, allows cutting in a flat piece ofwork an outline 10 defining the curve in the shape of a figure eight.

Said curve forming a figure eight defines the runway 11 illustrated inFIGS. 2 and 3, which runway forms the inner peripheral surface of theannular casing 12. The latter may move with reference to the axis of therotary piston, between the side walls 13 and 1-4, in parallelism withthe horizontal diameter of the casing. The bearings provided for thesliding of the casing are illustrated at 15 and 16. The throttledsections of the curve in the shape of a figure eight form thewedge-shaped guiding projections 17 and 18 which face each other andform on the runway projections directed towards each other and towardsthe axis of the piston P. In a manner corresponding to the,

speed reduction ratio equal to 1:3 selected for the toothed wheels 56(FIG. 1), of the cutting or milling system, I resort to a rotary pistonhaving three arms or three sides. The amplitude of the shifting of theannular casing 12 corresponds to the amplitude of the shifting of thecarriage 4 and the diameter of the rollers 19 carried by the rotarypiston corresponds to the diameter of the cutter 8.

Upon rotation of the piston in an anticlockwise direction, the volume ofthe chamber V1 (FIG. 2), increases up to a maximum volume V2 (FIG. 3).The reduction in FIGS. 2 and 3 are diagrammatic views of a machineprovided with a runway in the shape of a figure eight and associatedwith a three-armed piston, said figures corresponding to successivestages of operation,

FIG. 4 is a longitudinal section through line IVIV of FIG. 5illustrating a double unit including two rotary piston machines.

FIG. 5 is a cross-section through lines VV of FIG. 4,

FIGS. 6 and 7 are diagrammatic views of a modified embodiment at twostages of its operation.

The curve defining the runway inside the annular casing is produced bymeans of a milling system, said curve be ing illustrated for instance inFIG. 1 as a curve 1 in the shape of a figure eight. The connecting rod 2being caused to rotate, the carriage 4 is constrained to reciprocatepressure thus obtained ensures the suction of the mixture of fuel andair. Inside the chamber V3 showing a minimum volume, the compressedmixture is ignited at 20. The thrust exerted on the are 22 of the runwaydefining the annular casing, which are extends over the chamber V3,urges the wedge-shaped section 17 formed along the outer are 23 of therunway against the outer end of the arm 19 of the piston whereby arotary torque is transmitted to the piston.

When associating in series two operative units on the same shaft asillustrated in FIGS. 4 and 5 and angularly shifting the correspondingrotary pistons, operative thrusts are obtained in continuous alternationin the two units.

As illustrated in FIGS. 6 and 7, the rotary piston machine can operateas a compressor, which leads to the important advantage of producing anumber of operative strokes for each revolution of the piston. Uponignition of the fuel-and-air mixture in the cylinder chamber 24 of FIG.6, the two pistons 2526 are shifted towards the right hand side. Thisshifts simultaneously the annular casing 29 inserted between the endsfacing each other of the hollow piston rods 27 and 28 so that the rotarypiston is driven into rotation by said shiftng of the annular casing.The fuel-and-air mixture compressed by the rotation of the rotary pistonpasses out of the chamber V4 showing a minimum volume as illustrated inFIG. 7, and raises the valve head 30 so as to enter the cylinder chamber24 through the hollow piston rod. Upon continuation of the rotation ofthe piston, the mixture enters the other cylinder chamber.

What I claim is:

1. A rotary piston machine comprising an annular casing adapted toreciprocate along a predetermined elongated path and the inner surfaceof which forms a runway including two inwardly projecting diametricallyopposed wedge-shaped sections, sidewalls parallel with said path andclosing laterally the casing, a rotary piston revolve inside the casinground a stationary axis perpendicular to the side walls to therebyensure a positive relationship between the reciprocation of the casingand the rotation of the piston to thereby constrain the closed chambersto vary in volume, each extreme position of the casing on its pathcorresponding to the formation, between the Wedge-Shaped section locatedat the end of the path leading to said extreme position and the surfaceof the piston facing last-mentioned wedge-shaped section, of a chamberof a minimum volume while the other wedge-shaped section is operativelyengaged by a radial projection on the piston.

2. In a rotary piston machine as claimed in claim 1, adapted to operateas an internal combustion engine, the provision of igniting means inregistry with the location of the minimum volume chamber to produce theignition of a combustible mixture therein and thereby a shifting of thereciprocatable casing, the other wedgeshaped section of which urges thepiston into rotation.

3. In a rotary piston machine as claimed in claim 1 wherein the runwayis in the shape of a figure eight, the provision of three radial arms onthe piston, two of which extend to either side of one wedge-shapedsection of the runway on the casing, when the latter is in one of theextreme positions of its path and said Wedge-shaped section is nearerthe axis of the piston, to form the minimum volume chamber while thethird arm engages a side of the other wedge-shaped section lyingfurthest from the piston axis.

4. In combination with a rotary piston machine as claimed in claim 1adapted to act as a compressor, the provision of two cylinder and pistonunits extending outside the casing in alignment with the common axis ofthe two wedge-shaped sections, each unit including a piston rod engagingthe casing at a point registering with the cooperatin wedge-shapedsection and means for feeding a gasiform mixture compressed inside thechambers of the rotary piston machine into the cylinders of said units.

5. An arrangement for defining the outline of the runway of the casingof the machine claimed in claim 1, comprising a carriage adapted toreciprocate along a predetermined path, the length of which is equal tothat of the path of the casing, means controlling the reciprocation ofsaid carriage, interengaging toothed wheels pivotally carried by saidcarriage, a rod adapted to rock round the axis of one of said wheels, acutter revolvably carried by the outer end of said rod and adapted tocut the desired outline, the radius of said cutter being equal to theradius of curvature of the outer ends of the radial projections, thespeed reducing ratio between the wheels being equal to the number ofradial projections on the piston.

References Cited UNITED STATES PATENTS 1,054,729 3/1913 Whittinghill123-14 2,398,864 4/ 1946 Soher 123-50 2,583,633 1/1952 Cronin 123-142,863,426 12/1958 Summerlin 123-50 X 2,984,222 5/1961 Smith 91-210 XCARLTON R. CROYLE, Primary Examiner.

RALPH D. BLAKESLEE, Examiner.

1. A ROTARY PISTON MACHINE COMPRISING AN ANNULAR CASING ADAPTED TORECIPROCATE ALONG A PREDETERMINED ELONGATED PATH AND THE INNER SURFACEOF WHICH FORMS A RUNWAY INCLUDING TWO INWARDLY PROJECTING DIAMETRICALLYOPPOSED WEDGE-SHAPED SECTIONS, SIDEWALLS PARALLEL WITH SAID PATH ANDCLOSING LATERALLY THE CASING, A ROTARY PISTON INCLUDING A PLURALITY OFSUBSTANTIALLY RADIAL PROJECTIONS ENGAGING SAID RUNWAY AND FORMING WITHTHE LATTER A PLURALITY OF CLOSED CHAMBERS, SAID PISTON BEING ADAPTED TOREVOLVE INSIDE THE CASING ROUND A STATIONARY AXIS PERPENDICULAR TO THESIDE WALLS TO THEREBY ENSURE A POSITIVE RELATIONSHIP BETWEEN THERECIPROCATION OF THE CASING AND THE ROTATION OF THE PISTON TO THEREBYCONSTRAIN THE CLOSED